What's the proper way to refer to the form of a word that's improperly punctuated?

Question

Example sentence:

The Adventure's of Huckleberry Finn

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My dilemma:

I would like to convey to the writer of the example sentence that the word Adventure's, in its current _____ form, is grammatically incorrect (as opposed to its should-be plural form).

At first I started to use the word possessive to describe the form, but then I started thinking¹ that maybe, in the writer's mind, the word was in fact not written to represent possession but rather as a contraction of the words Adventure and is. In the latter case, I believe using the word contractional would be more appropriate than using the word possessive but since I don't know what the writer was (hypothetically) thinking when they wrote the word, I don't know which adjective to choose, if either.

I realize that chances are the writer just accidentally added an apostrophe where they shouldn't have, but that's neither here nor there.

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My question:

What's the best word to use to describe the current, incorrect form of the word Adventures as described above? Is there an all-encompassing word that would be a better fit than the words possessive, contractional, or a combination thereof?

Thanks!

¹ Yes, it hurt. ;)

Answer 1

Apostrophize - punctuate (a word) with an apostrophe

I would like to convey to the writer of the example sentence that the word Adventure's, in its current apostrophized form, is grammatically incorrect (as opposed to its should-be plural form).

Answer 2

This is a grammatical error if the writer of the phrase wouldn't be able to percieve the problem if re-reading it, a spelling mistake if it was merely a careless oversight.

In other words, the kind of mistake it was depends on the cognitive state of the writer at the time of the mistake.

As regards your question of how to describe what is going on, the problem is that the possessive (or genitive) singular of the noun has been substituted for the nominative (or basic) plural, and that the distinction is difficult to maintain because the two forms are homophones. This description is true whether the error was in grammar or in spelling.

Answer 3

Misspelled. The plural suffix -s isn't usually spelled with an apostrophe in this context.

Punctuation punctuates. It separates. It shows relationships between units of speech in written form. The periods in-between these sentences punctuate, and so does the comma in the middle of this sentence. The apostrophe in The Adventure's of Huckleberry Finn does no such thing.

For elaboration on this point, please see Geoffrey Pullum's Being an Apostrophe at Lingua Franca.